Sources / Suggested Reading / Further Information
Please note that this is an evolving list with new additions added frequently.

Websites:

http://scca.com/ - Sports Car Club of America
http://www.bmwcca.org/ - BMW Car Club of America
http://www.mustang.org/ - Mustang Club of America
http://www.pca.org/ - Porsche Club of America
http://www.clubmiata.com/ - National Miata Club
http://www.sema.org/ - SEMA
http://www.classiccarclub.org/ - Classic Car Club of America
http://www.ferrariclubofamerica.org - Ferrari Club of America
http://www.alfaclub.org/ - Alfa Clubhouse

http://en.wikipedia.org/ - Wikipedia.org
http://www.pittsburghvintagegrandprix.com/ - Pittsburgh Vintage Grand Prix Association
http://www.jefferson500.com/ - Jefferson 500
http://www.grandprixfestival.com/ - Grand Prix Festival of Watkins Glen
http://www.zippo.com/ - Zippo U.S. Vintage Grand Prix of Watkins Glen
http://www.krausebooks.com/ - Krause Publications
http://www.rrab.com/ - Rolls-Royce and Bentley Information
http://Oldracingcars.com/ - OldRacingCars.com
http://www.maranello-literature.com - Maranello Literature
http://www.ferrariworld.com/ - Ferrari World
http://www.oldcartrader.com/ - Old Car Trader
http://www.musclecarclub.com/ - Muscle Car Club
http://www.modernmusclecars.net/ - Modern Muscle Cars
http://www.centerlinealfa.com/ Alfa Romeo - Parts
http://gunnersgarage.oldcarsweekly.com/ - Gunner's Garage
http://www.nada.com/ - N.A.D.A. Official Used Car Guide Company
http://www.nada.org - National Automobile Dealers Association

http://www.virclub.com/vir/ - Virginia International Raceway
http://www.beaverun.com/ - BeaveRun Motorsports Complex
http://www.theglen.com/ - Watkins Glen International
http://www.morosomotorsportspark.com/ - Moroso Motorsports Park
http://www.summitpoint-raceway.com/ - Summit Point Motorsports Park
http://www.laguna-seca.com/ - Mazda Raceway Laguna Seca - Monterey, California

http://www.pebblebeachconcours.net/ - Pebble Beach Concours d'Elegance
http://www.meadowbrookconcours.org/ - Meadow Brook Concours d'Elegance
http://www.hhiconcours.com/ - Hilton Head Island Concours d'Elegance & Motoring Festival
http://www.greenwichconcours.com/ - Greenwich Concours d'Elegance
http://www.concourseast.org/ - Concours d'Elegance of the Eastern United States
http://www.radnorconcours.org/ - Radnor Hunt Concours d'Elegance
http://www.quaillodge.com/ - Carmel CA - Quail Lodge - A Motorsport Gathering
http://www.ameliaconcours.org/ - Amelia Island Concours d'Elegance
http://www.cavallino.com/ - Cavallino Magazine & Classic
http://www.palmbeachconcours.com - The Palm Beach International

http://www.goodingco.com/ - Gooding & Company
http://www.rmauctions.com/ - RM Auctions
http://www.russoandsteele.com/ - Russo & Steele Collector Automobile Auctions
http://www.bonhams.com/ - Bonhams & Butterfields Auction
http://www.wwgauctions.com/ - World Wide Group Auctioneers
http://www.christies.com/ - Christie's
http://www.barrett-jackson.com/ - Barrett-Jackson Auctions
http://www.blackhawkcollection.com/ - Blackhawk Collection
http://www.blackhawkmuseum.org/ - Blackhawk Museum
http://www.pottsauction.com/ - Potts Auction

Magazines - Print and Online: http://www.sportscarmarket.com/ - Sports Car Market
http://www.autocarmag.com/ - Autocar
http://www.motortrend.com/ - Motor Trend
http://www.roadandtrack.com/ - Road and Track
http://www.automobile.com/ - Automobile.com. Everything Automobile
http://www.classicandsportscar.com/ - Classic & Sports Car
http://www.canadiandriver.com/ - CanadianDriver
http://www.classicdriver.de/ - Classic Driver
http://www.classiccar.com/ - ClassicCar.com
http://www.autoevents.org/ - Auto Events Magazine
http://www.motorsport.com/ - Motorsport.com News Channel
http://www.speedtv.com/ - SpeedTV
http://www.cardesignnews.com/ - Car Design News
http://www.oldcarsweekly.com/ - Old Cars Weekly
http://www.hemmings.com/ - Hemmings Motor News
http://www.carcraft.com/ - Car Craft Magazine
https://consumerguide.com/ - Consumer Guide® Automotive
http://www.edmunds.com/ - Edmunds.com
http://www.prewarcar.com/ - PreWar Car
http://www.automobilemag.com/ - Automobile Magazine - New Car Specifications
http://www.theautochannel.com/ - The Auto Channel

Books Encyclopedia of American Cars
by The Editoros of Consumer Guide
ISBN: 0-7853-6275-4

Targa Florio 'The Post-War Years' 1948-1973
by R. M. Clarke
ISBN: 1855204975

Complete Catalog of British Cars, 1895-1975
by David Culshaw
ISBN: 1874105936

Standard Catalog of Imported Cars 1946-2002
By Mike Covello
ISBN: 0-87341-605-8

Standard Catalog of Pontiac
by John Gunnell and Ron Kowalke
ISBN: 0-87341-369-5

Standard Catalog of Chrysler
by James T. Lenzke
ISBN: 0-87341-882-4

Standard Catalog of Buick
by John Gunnell
ISBN: 0-87349-760-0

The Classic Citroens, 1935-1975
by John Reynolds
ISBN: 0786421711

Porsche 911 Buyer's Guide
by Randy Leffingwell
ISBN: 0760309477

Standard Catalog of Pontiac
by John Gunnell
ISBN: 0-87349-263-3

Weber Carburetors
by Verlon P. Braden
ISBN: 0895863774

Catalog of American Car Id Numbers 1950-59
by Cars & Parts Magazine
ISBN: 188052404X

Standard Catalog of Chevrolet
by John Gunnell
ISBN: 0-87349-680-9

Standard Catalog of Cadillac
by John Gunnell
ISBN: 0-87349-289-7

Maserati
by Jill C. Wheeler
ISBN: 1591975808

Maserati Cars 1971-1982 -Performance Portfolio
by R.M. Clarke
ISB: 1855206005

Racing Maseratis
by Giancarlo Raggiani
ISBN: 887911252X

Standard Catalog of Ford
by John Gunnell
ISBN: 0-87349-452-0

Standard Catalog American Cars 1946-1975
by Jon Gunnell
ISBN: 0-87349-461-X

Standard Catalog of American Motors/1902-1987
by John Gunnell
ISBN: 0-87341-232-X

Sports Racing Cars
by Anthony Pritchard
ISBN: 1 84425 138 1

Delahaye Styling and Design
by Richard S. Adatto, Diana E. Meredith, and Michael Furman
ISBN: 1854432214

Delahaye La Belle Carrosserie Francais
by Jean-Paul Tissot
ASIN: B000MMBDN4

Talbot, des Talbot-Darracq aux Talbot-Lago
by Alain Spitz
ISBN: 2851201700

Duesenberg
by Dennis Adler
ISBN: 0873493885

Auburn Cord Duesenberg
by Don Butler
ISBN: 0879387017

Duesenberg: The Mightiest American Motor Car
by J.L. Elbert
ISBN: 0911160493

Alfa Romeo Owner's Bible: A Hands-On Guide to Getting the Most from Your Alfa
by Pat Braden
ISBN: 0837607078

Alfa Romeo Tipo33: The Development,Racing and Chassis History
by Ed Mcdonough
ISBN: 1904788718

Alfa Romeo
by David Styles
ISBN: 0750919582

Kurtis-Kraft Masterworks of Speed and Style
by Gordon Eliot White
ISBN 0-7603-0910-8

Offenhauser
by Gordon Eliot White
ISBN: 0-7603-1918-9

1950s Motorsport in Colour
by Martyn Wainwright
ISBN: 1-904788-15-7

Vintage American Road Racing Cars 1950-1970
by Harold W. Pace and Mark R. Brinker
ISBN: 0-7603-1783-6

Lotus The Competition Cars
by Anthony Pritchard

The Hemmings Book of Postwar American Independents
ISBN: 1-591150-01-9

The Encyclopedia of Classic Cars
general editor: David Lillywhite
ISBN: 1-57145-990-1

Corvette - America's Sports Car
by Randy Leffingwell
ISBN: 0-7603-1352-0

Ferrari, Formula Cars
by Giulio Schmidt
ISBN: 0-87938-967-2

The Bentley R-Type
by Bernard L. King

The Bentley S1 and Rolls-Royce Silver Cloud I
by Davide Bassoli & Bernard L. King

The Derby Built Bentleys
by Bernard L. King

The Rolls-Royce Silver Dawn & Silver Wraith
by Bernard L. King

The Rolls-Royce 20/25 H.P.
by Tom Clarke

Bugatti Magnum
by Hugh Conway with Maurice Sauzay

Bugatti - le Pur Sang des Automobiles
by Conway

Grand Marques Bugatti
by Conway